Abstract: A variable air flow/multiple zone HVAC air terminal system has a plurality of air passageways for conditioned air, bypass air, and optionally outside air, for separate distribution to outlet passageways to the multiple zones. A corresponding plurality of rotating cylindrical air dampeners selectively controls air flow from the conditioned air, bypass air, and outside air passageways to respective ones of the plurality of outlet air passageways corresponding to respective zones. Damper drivers cause rotation of the rotating air dampeners in response to sensed air conditions in the respective zones to control ratios and volume flow rates of the conditioned, bypass, and outside air fed to the respective outlet air passageways, so rotation of respective ones of the rotating air dampers selectively varies air flow to the respective outlet air passageways.

Abstract: A variable air flow/multiple zone HVAC air terminal system has a plurality of air passageways for conditioned air, bypass air, and optionally outside air, for separate distribution to outlet passageways to the multiple zones. A corresponding plurality of rotating cylindrical air dampeners selectively controls air flow from the conditioned air, bypass air, and outside air passageways to respective ones of the plurality of outlet air passageways corresponding to respective zones. Damper drivers cause rotation of the rotating air dampeners in response to sensed air conditions in the respective zones to control ratios and volume flow rates of the conditioned, bypass, and outside air fed to the respective outlet air passageways, so rotation of respective ones of the rotating air dampers selectively varies air flow to the respective outlet air passageways.

Abstract: A process for recovery of combustionable coal from fine coal such as frequently considered waste coal from mining operations includes drying and classifying the raw coal into ultra-fine and fine size classes. The ultra-fine size class is directed to a collector and further separated in a strictly dry manner while the fine size class is separated in a flotation apparatus to divide out the coal and ash therein which are subsequently screened, with or without washing and drying at that time. The screened fine size coal, after being dried, is collected in a stock pile, as is also any dry ultra-fine size coal as discharged by the collector.